github.com/rabbouni145/gg@v0.47.1/docs/content/en/templates/shortcode-templates.md (about) 1 --- 2 title: Create Your Own Shortcodes 3 linktitle: Shortcode Templates 4 description: You can extend Hugo's built-in shortcodes by creating your own using the same templating syntax as that for single and list pages. 5 date: 2017-02-01 6 publishdate: 2017-02-01 7 lastmod: 2017-02-01 8 categories: [templates] 9 keywords: [shortcodes,templates] 10 menu: 11 docs: 12 parent: "templates" 13 weight: 100 14 weight: 100 15 sections_weight: 100 16 draft: false 17 aliases: [] 18 toc: true 19 --- 20 21 Shortcodes are a means to consolidate templating into small, reusable snippets that you can embed directly inside of your content. In this sense, you can think of shortcodes as the intermediary between [page and list templates][templates] and [basic content files][]. 22 23 {{% note %}} 24 Hugo also ships with built-in shortcodes for common use cases. (See [Content Management: Shortcodes](/content-management/shortcodes/).) 25 {{% /note %}} 26 27 ## Create Custom Shortcodes 28 29 Hugo's built-in shortcodes cover many common, but not all, use cases. Luckily, Hugo provides the ability to easily create custom shortcodes to meet your website's needs. 30 31 {{< youtube Eu4zSaKOY4A >}} 32 33 ### File Placement 34 35 To create a shortcode, place an HTML template in the `layouts/shortcodes` directory of your [source organization][]. Consider the file name carefully since the shortcode name will mirror that of the file but without the `.html` extension. For example, `layouts/shortcodes/myshortcode.html` will be called with either `{{</* myshortcode /*/>}}` or `{{%/* myshortcode /*/%}}` depending on the type of parameters you choose. 36 37 ### Shortcode Template Lookup Order 38 39 Shortcode templates have a simple [lookup order][]: 40 41 1. `/layouts/shortcodes/<SHORTCODE>.html` 42 2. `/themes/<THEME>/layouts/shortcodes/<SHORTCODE>.html` 43 44 ### Positional vs Named Parameters 45 46 You can create shortcodes using the following types of parameters: 47 48 * Positional parameters 49 * Named parameters 50 * Positional *or* named parameters (i.e, "flexible") 51 52 In shortcodes with positional parameters, the order of the parameters is important. If a shortcode has a single required value (e.g., the `youtube` shortcode below), positional parameters work very well and require less typing from content authors. 53 54 For more complex layouts with multiple or optional parameters, named parameters work best. While less terse, named parameters require less memorization from a content author and can be added in a shortcode declaration in any order. 55 56 Allowing both types of parameters (i.e., a "flexible" shortcode) is useful for complex layouts where you want to set default values that can be easily overridden by users. 57 58 ### Access Parameters 59 60 All shortcode parameters can be accessed via the `.Get` method. Whether you pass a key (i.e., string) or a number to the `.Get` method depends on whether you are accessing a named or positional parameter, respectively. 61 62 To access a parameter by name, use the `.Get` method followed by the named parameter as a quoted string: 63 64 ``` 65 {{ .Get "class" }} 66 ``` 67 68 To access a parameter by position, use the `.Get` followed by a numeric position, keeping in mind that positional parameters are zero-indexed: 69 70 ``` 71 {{ .Get 0 }} 72 ``` 73 74 `with` is great when the output depends on a parameter being set: 75 76 ``` 77 {{ with .Get "class"}} class="{{.}}"{{ end }} 78 ``` 79 80 `.Get` can also be used to check if a parameter has been provided. This is 81 most helpful when the condition depends on either of the values, or both: 82 83 ``` 84 {{ or .Get "title" | .Get "alt" | if }} alt="{{ with .Get "alt"}}{{.}}{{else}}{{.Get "title"}}{{end}}"{{ end }} 85 ``` 86 87 #### `.Inner` 88 89 If a closing shortcode is used, the `.Inner` variable will be populated with all of the content between the opening and closing shortcodes. If a closing shortcode is required, you can check the length of `.Inner` as an indicator of its existence. 90 91 A shortcode with content declared via the `.Inner` variable can also be declared without the inline content and without the closing shortcode by using the self-closing syntax: 92 93 ``` 94 {{</* innershortcode /*/>}} 95 ``` 96 97 #### `.Params` 98 99 The `.Params` variable in shortcodes contains the list parameters passed to shortcode for more complicated use cases. You can also access higher-scoped parameters with the following logic: 100 101 `$.Params` 102 : these are the parameters passed directly into the shortcode declaration (e.g., a YouTube video ID) 103 104 `$.Page.Params` 105 : refers to the page's params; the "page" in this case refers to the content file in which the shortcode is declared (e.g., a `shortcode_color` field in a content's front matter could be accessed via `$.Page.Params.shortcode_color`). 106 107 `$.Page.Site.Params` 108 : refers to global variables as defined in your [site's configuration file][config]. 109 110 #### `.IsNamedParams` 111 112 The `.IsNamedParams` variable checks whether the shortcode declaration uses named parameters and returns a boolean value. 113 114 For example, you could create an `image` shortcode that can take either a `src` named parameter or the first positional parameter, depending on the preference of the content's author. Let's assume the `image` shortcode is called as follows: 115 116 ``` 117 {{</* image src="images/my-image.jpg"*/>}} 118 ``` 119 120 You could then include the following as part of your shortcode templating: 121 122 ``` 123 {{ if .IsNamedParams }} 124 <img src="{{.Get "src" }}" alt=""> 125 {{ else }} 126 <img src="{{.Get 0}}" alt=""> 127 {{ end }} 128 ``` 129 130 See the [example Vimeo shortcode][vimeoexample] below for `.IsNamedParams` in action. 131 132 {{% warning %}} 133 While you can create shortcode templates that accept both positional and named parameters, you *cannot* declare shortcodes in content with a mix of parameter types. Therefore, a shortcode declared like `{{</* image src="images/my-image.jpg" "This is my alt text" */>}}` will return an error. 134 {{% /warning %}} 135 136 You can also use the variable `.Page` to access all the normal [page variables][pagevars]. 137 138 A shortcodes can also be nested. In a nested shortcode, you can access the parent shortcode context with [`.Parent` variable][shortcodesvars]. This can be very useful for inheritance of common shortcode parameters from the root. 139 140 ### Checking for Existence 141 142 You can check if a specific shortcode is used on a page by calling `.HasShortcode` in that page template, providing the name of the shortcode. This is sometimes useful when you want to include specific scripts or styles in the header that are only used by that shortcode. 143 144 ## Custom Shortcode Examples 145 146 The following are examples of the different types of shortcodes you can create via shortcode template files in `/layouts/shortcodes`. 147 148 ### Single-word Example: `year` 149 150 Let's assume you would like to keep mentions of your copyright year current in your content files without having to continually review your markdown. Your goal is to be able to call the shortcode as follows: 151 152 ``` 153 {{</* year */>}} 154 ``` 155 156 {{< code file="/layouts/shortcodes/year.html" >}} 157 {{ now.Format "2006" }} 158 {{< /code >}} 159 160 ### Single Positional Example: `youtube` 161 162 Embedded videos are a common addition to markdown content that can quickly become unsightly. The following is the code used by [Hugo's built-in YouTube shortcode][youtubeshortcode]: 163 164 ``` 165 {{</* youtube 09jf3ow9jfw */>}} 166 ``` 167 168 Would load the template at `/layouts/shortcodes/youtube.html`: 169 170 {{< code file="/layouts/shortcodes/youtube.html" >}} 171 <div class="embed video-player"> 172 <iframe class="youtube-player" type="text/html" width="640" height="385" src="http://www.youtube.com/embed/{{ index .Params 0 }}" allowfullscreen frameborder="0"> 173 </iframe> 174 </div> 175 {{< /code >}} 176 177 {{< code file="youtube-embed.html" copy="false" >}} 178 <div class="embed video-player"> 179 <iframe class="youtube-player" type="text/html" 180 width="640" height="385" 181 src="http://www.youtube.com/embed/09jf3ow9jfw" 182 allowfullscreen frameborder="0"> 183 </iframe> 184 </div> 185 {{< /code >}} 186 187 ### Single Named Example: `image` 188 189 Let's say you want to create your own `img` shortcode rather than use Hugo's built-in [`figure` shortcode][figure]. Your goal is to be able to call the shortcode as follows in your content files: 190 191 {{< code file="content-image.md" >}} 192 {{</* img src="/media/spf13.jpg" title="Steve Francia" */>}} 193 {{< /code >}} 194 195 You have created the shortcode at `/layouts/shortcodes/img.html`, which loads the following shortcode template: 196 197 {{< code file="/layouts/shortcodes/img.html" >}} 198 <!-- image --> 199 <figure {{ with .Get "class" }}class="{{.}}"{{ end }}> 200 {{ with .Get "link"}}<a href="{{.}}">{{ end }} 201 <img src="{{ .Get "src" }}" {{ if or (.Get "alt") (.Get "caption") }}alt="{{ with .Get "alt"}}{{.}}{{else}}{{ .Get "caption" }}{{ end }}"{{ end }} /> 202 {{ if .Get "link"}}</a>{{ end }} 203 {{ if or (or (.Get "title") (.Get "caption")) (.Get "attr")}} 204 <figcaption>{{ if isset .Params "title" }} 205 <h4>{{ .Get "title" }}</h4>{{ end }} 206 {{ if or (.Get "caption") (.Get "attr")}}<p> 207 {{ .Get "caption" }} 208 {{ with .Get "attrlink"}}<a href="{{.}}"> {{ end }} 209 {{ .Get "attr" }} 210 {{ if .Get "attrlink"}}</a> {{ end }} 211 </p> {{ end }} 212 </figcaption> 213 {{ end }} 214 </figure> 215 <!-- image --> 216 {{< /code >}} 217 218 Would be rendered as: 219 220 {{< code file="img-output.html" copy="false" >}} 221 <figure> 222 <img src="/media/spf13.jpg" /> 223 <figcaption> 224 <h4>Steve Francia</h4> 225 </figcaption> 226 </figure> 227 {{< /code >}} 228 229 ### Single Flexible Example: `vimeo` 230 231 ``` 232 {{</* vimeo 49718712 */>}} 233 {{</* vimeo id="49718712" class="flex-video" */>}} 234 ``` 235 236 Would load the template found at `/layouts/shortcodes/vimeo.html`: 237 238 {{< code file="/layouts/shortcodes/vimeo.html" >}} 239 {{ if .IsNamedParams }} 240 <div class="{{ if .Get "class" }}{{ .Get "class" }}{{ else }}vimeo-container{{ end }}"> 241 <iframe src="//player.vimeo.com/video/{{ .Get "id" }}" allowfullscreen></iframe> 242 </div> 243 {{ else }} 244 <div class="{{ if len .Params | eq 2 }}{{ .Get 1 }}{{ else }}vimeo-container{{ end }}"> 245 <iframe src="//player.vimeo.com/video/{{ .Get 0 }}" allowfullscreen></iframe> 246 </div> 247 {{ end }} 248 {{< /code >}} 249 250 Would be rendered as: 251 252 {{< code file="vimeo-iframes.html" copy="false" >}} 253 <div class="vimeo-container"> 254 <iframe src="//player.vimeo.com/video/49718712" allowfullscreen></iframe> 255 </div> 256 <div class="flex-video"> 257 <iframe src="//player.vimeo.com/video/49718712" allowfullscreen></iframe> 258 </div> 259 {{< /code >}} 260 261 ### Paired Example: `highlight` 262 263 The following is taken from `highlight`, which is a [built-in shortcode][] that ships with Hugo. 264 265 {{< code file="highlight-example.md" >}} 266 {{</* highlight html */>}} 267 <html> 268 <body> This HTML </body> 269 </html> 270 {{</* /highlight */>}} 271 {{< /code >}} 272 273 The template for the `highlight` shortcode uses the following code, which is already included in Hugo: 274 275 ``` 276 {{ .Get 0 | highlight .Inner }} 277 ``` 278 279 The rendered output of the HTML example code block will be as follows: 280 281 {{< code file="syntax-highlighted.html" copy="false" >}} 282 <div class="highlight" style="background: #272822"><pre style="line-height: 125%"><span style="color: #f92672"><html></span> 283 <span style="color: #f92672"><body></span> This HTML <span style="color: #f92672"></body></span> 284 <span style="color: #f92672"></html></span> 285 </pre></div> 286 {{< /code >}} 287 288 {{% note %}} 289 The preceding shortcode makes use of a Hugo-specific template function called `highlight`, which uses [Pygments](http://pygments.org) to add syntax highlighting to the example HTML code block. See the [developer tools page on syntax highlighting](/tools/syntax-highlighting/) for more information. 290 {{% /note %}} 291 292 ### Nested Shortcode: Image Gallery 293 294 Hugo's [`.Parent` shortcode variable][parent] returns a boolean value depending on whether the shortcode in question is called within the context of a *parent* shortcode. This provides an inheritance model for common shortcode parameters. 295 296 The following example is contrived but demonstrates the concept. Assume you have a `gallery` shortcode that expects one named `class` parameter: 297 298 {{< code file="layouts/shortcodes/gallery.html" >}} 299 <div class="{{.Get "class"}}"> 300 {{.Inner}} 301 </div> 302 {{< /code >}} 303 304 You also have an `img` shortcode with a single named `src` parameter that you want to call inside of `gallery` and other shortcodes, so that the parent defines the context of each `img`: 305 306 {{< code file="layouts/shortcodes/img.html" >}} 307 {{- $src := .Get "src" -}} 308 {{- with .Parent -}} 309 <img src="{{$src}}" class="{{.Get "class"}}-image"> 310 {{- else -}} 311 <img src="{{$src}}"> 312 {{- end }} 313 {{< /code >}} 314 315 You can then call your shortcode in your content as follows: 316 317 ``` 318 {{</* gallery class="content-gallery" */>}} 319 {{</* img src="/images/one.jpg" */>}} 320 {{</* img src="/images/two.jpg" */>}} 321 {{</* /gallery */>}} 322 {{</* img src="/images/three.jpg" */>}} 323 ``` 324 325 This will output the following HTML. Note how the first two `img` shortcodes inherit the `class` value of `content-gallery` set with the call to the parent `gallery`, whereas the third `img` only uses `src`: 326 327 ``` 328 <div class="content-gallery"> 329 <img src="/images/one.jpg" class="content-gallery-image"> 330 <img src="/images/two.jpg" class="content-gallery-image"> 331 </div> 332 <img src="/images/three.jpg"> 333 ``` 334 335 ## More Shortcode Examples 336 337 More shortcode examples can be found in the [shortcodes directory for spf13.com][spfscs] and the [shortcodes directory for the Hugo docs][docsshortcodes]. 338 339 [basic content files]: /content-management/formats/ "See how Hugo leverages markdown--and other supported formats--to create content for your website." 340 [built-in shortcode]: /content-management/shortcodes/ 341 [config]: /getting-started/configuration/ "Learn more about Hugo's built-in configuration variables as well as how to us your site's configuration file to include global key-values that can be used throughout your rendered website." 342 [Content Management: Shortcodes]: /content-management/shortcodes/#using-hugo-s-built-in-shortcodes "Check this section if you are not familiar with the definition of what a shortcode is or if you are unfamiliar with how to use Hugo's built-in shortcodes in your content files." 343 [source organization]: /getting-started/directory-structure/#directory-structure-explained "Learn how Hugo scaffolds new sites and what it expects to find in each of your directories." 344 [docsshortcodes]: https://github.com/gohugoio/hugo/tree/master/docs/layouts/shortcodes "See the shortcode source directory for the documentation site you're currently reading." 345 [figure]: /content-management/shortcodes/#figure 346 [hugosc]: /content-management/shortcodes/#using-hugo-s-built-in-shortcodes 347 [lookup order]: /templates/lookup-order/ "See the order in which Hugo traverses your template files to decide where and how to render your content at build time" 348 [pagevars]: /variables/page/ "See which variables you can leverage in your templating for page vs list templates." 349 [parent]: /variables/shortcodes/ 350 [shortcodesvars]: /variables/shortcodes/ "Certain variables are specific to shortcodes, although most .Page variables can be accessed within your shortcode template." 351 [spfscs]: https://github.com/spf13/spf13.com/tree/master/layouts/shortcodes "See more examples of shortcodes by visiting the shortcode directory of the source for spf13.com, the blog of Hugo's creator, Steve Francia." 352 [templates]: /templates/ "The templates section of the Hugo docs." 353 [vimeoexample]: #single-flexible-example-vimeo 354 [youtubeshortcode]: /content-management/shortcodes/#youtube "See how to use Hugo's built-in YouTube shortcode."